After Hodgkin lymphoma has been diagnosed, tests are done to find out if cancer cells have spread within the lymph system or to other parts of the body.

The process used to find out if cancer has spread within the lymph system or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage to plan treatment. The results of the tests and procedures done to diagnose and stage Hodgkin lymphoma are used to help make decisions about treatment.

There are three ways that cancer spreads in the body.

Cancer can spread through tissue, the lymph system, and the blood:

• Tissue. The cancer spreads from where it began by growing into nearby areas.
• Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
• Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

The following stages are used for Hodgkin lymphoma:

Stage I

Stage I Hodgkin lymphoma is divided into stages I and IE.

• In stage I, cancer is found in one of the following places in the lymph system:
  • One or more lymph nodes in a group of lymph nodes.
  • Waldeyer's ring.
  • Thymus.
  • Spleen.
• In stage IE, cancer is found in one area outside the lymph system.

Stage II

Stage II Hodgkin lymphoma is divided into stages II and IIE.

• In stage II, cancer is found in two or more groups of lymph nodes that are either above the diaphragm or below the diaphragm.
• In stage IIE, cancer has spread from a group of lymph nodes to a nearby area that is outside the lymph system. Cancer may have spread to other lymph node groups on the same side of the diaphragm.

In stage II, the term bulky disease refers to a larger tumor mass. The size of the tumor mass that is referred to as bulky disease varies based on the type of lymphoma.

Stage III

In stage III Hodgkin lymphoma, cancer is found:

• in groups of lymph nodes both above and below the diaphragm; or
• in lymph nodes above the diaphragm and in the spleen.

Stage IV

In stage IV Hodgkin lymphoma, cancer:

• has spread throughout one or more organs outside the lymph system; or
• is found in two or more groups of lymph nodes that are either above the diaphragm or below the diaphragm and in one organ that is outside the lymph system and not near the affected lymph nodes; or
• is found in groups of lymph nodes both above and below the diaphragm and in any organ that is outside the lymph system; or
• is found in the liver, bone marrow, more than one place in the lung, or cerebrospinal fluid (CSF). The cancer has not spread directly into the liver, bone marrow, lung, or CSF from nearby lymph nodes.

Hodgkin lymphoma may be grouped for treatment as follows:

Early Favorable

Early favorable Hodgkin lymphoma is stage I or stage II, without risk factors that increase the chance that the cancer will come back after it is treated.

Early Unfavorable

Early unfavorable Hodgkin lymphoma is stage I or stage II with one or more of the following risk factors that increase the chance that the cancer will come back after it is treated:

• Having a tumor in the chest that is larger than 1/3 of the width of the chest or is at least 10 centimeters.
• Having cancer in an organ other than the lymph nodes.
• Having a high sedimentation rate (in a sample of blood, the red blood cells settle to the bottom of the test tube more quickly than normal).
• Having three or more lymph nodes with cancer.
• Having B symptoms (fever for no known reason, weight loss for no known reason, or drenching night sweats).

Advanced

Advanced Hodgkin lymphoma is stage III or stage IV. Advanced favorable Hodgkin lymphoma means that the patient has 0–3 of the risk factors below. Advanced unfavorable Hodgkin lymphoma means that the patient has 4 or more of the risk factors below. The more risk factors a patient has, the more likely it is that the cancer will come back after it is treated:

• Having a low blood albumin level (below 4).
• Having a low hemoglobin level (below 10.5).
• Being male.
• Being aged 45 years or older.
• Having stage IV disease.
• Having a high white blood cell count (15,000 or higher).
• Having a low lymphocyte count (below 600 or less than 8% of the white blood cell count).

Hodgkin lymphoma can recur (come back) after it has been treated.

The cancer may come back in the lymph system or in other parts of the body.